Several modern display technologies are used to display moving, or “video,” images, such as liquid-crystal displays (LCDs) (which are suitable for either front or rear projection or direct view), DMDs (which are suitable for either front or rear projection as part of a spatial light modulator, or SLM, -based projector system) or plasma displays (which are suitable only for direct view). These display technologies differ fundamentally from the traditional cathode ray tube (CRT) in that they emit light continuously while displaying a single video frame. In contrast, a CRT emits a short burst of light once per video frame with intervening periods of relative darkness. Though the duration of the burst of light is short, its intensity is very high, so a CRT is capable of producing bright images despite the short duration of the burst of light.
In continuous-light-emitting video displays, the continuous emission of light can lead to significant degradation of video image quality. Motion of objects in the video image causes adjacent video frames to contain different images, resulting in the blurring of images, particularly at their edges. The image degrades as a direct function of the speed of the motion. Past some point, the objects moving in the image can no longer be discerned.
One prior art technique for reducing this blurring of the image involves generating and displaying interpolated images for each video frame. Unfortunately, generating interpolated images requires significant computation and storage capability and thus adds substantial complexity and cost to any device having that capability.
What is needed in the art is a way to increase the sharpness of a video image that requires less computation and storage capability than does interpolation of images. What is needed in the art is a way to increase the sharpness of a video image without having to compare adjacent frames. More generally, what is needed in the art is a way to process the frames of a video image such that they are perceived as being sharper when they are displayed on a continuous-light-emitting video display.